Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 12/5/2005
Publication Date: 12/4/2005
Citation: Neill, J.D., Ridpath, J.F., Bendfeldt, S. 2005. Identification of genes with altered expression in bovine BL3 cells following infection with different strains of BVDV type 2 [abstract]. 86th Annual Meeting of the Conference of Research Workers in Animal Diseases. p. 129. Interpretive Summary:
Technical Abstract: In the field, infection with noncytopathic BVDV results in a transient lymphoid depletion and immunosuppression that can increase the severity of secondary infections with other viruses or bacteria. The lymphoid depletion is especially notable with the virulent BVDV type 2 strains that cause severe acute disease. Immunosuppression leads to greater death loss, productivity loss and higher veterinary treatment costs to producers. The mechanisms by which BVDV causes lymphopenia and immunosuppression are unknown. We have employed serial analysis of gene expression (SAGE), a powerful method for global gene expression analysis, to examine gene expression changes in bovine lymphoid cells following infection with noncytopathic BVDV type 2. For this study, we used the B cell lymphoma cell line BL3. We constructed and sequenced SAGE libraries from noninfected BL3 cells and BL3 cells acutely infected with BVDV2 strains 28508 (noncytopathic), and 296c (cytopathic). The expression profiling of the non-infected BL3 cells showed the normal levels of gene expression. Most of the genes that are characteristic of this cell type and integral to their function were identified. Comparison of the SAGE databases from noninfected and BVDV2-infected BL3 cells revealed genes that were differentially expressed. Real-time PCR was used to confirm the altered expression levels of selected genes. Where antibodies were available that recognized bovine proteins, western immunoblots were done to determine affect on protein levels. Of interest are the elevated expression levels of two genes that negatively regulate B cell receptor signaling, indicating a possible mechanism behind BVDV-induced immunosuppression. Studies are currently underway to examine which gene expression changes affect cellular function and/or contribute to pathologies observed in BVDV-infected animals.